Hi guys,
I am trying to create a coding which allows users to upload and download files into mysql server, but I came across some errors. The coding itself works fine on the surface, but when I uploaded the file into mysql and download them, the contents of the downloaded file was different from the original file that was upload. One good example would be when I upload txt file or doc file. I was stuck on this for quite a few days without any leads.
Here are the codes:
index.html
<form action="add_file.php" method="post" enctype="multipart/form-data">
<input type="file" name="uploaded_file"><br>
<input type="submit" value="Upload file">
</form>
<p>
<a href="list_files.php">See all files</a>
</p>
add_file.php
<?php
// Check if a file has been uploaded
if(isset($_FILES['uploaded_file'])) {
// Make sure the file was sent without errors
if($_FILES['uploaded_file']['error'] == 0) {
// Connect to the database
$dbLink = new mysqli('localhost', 'root', 'pwd', 'myTable');
if(mysqli_connect_errno()) {
die("MySQL connection failed: ". mysqli_connect_error());
}
// Gather all required data
$name = $dbLink->real_escape_string($_FILES['uploaded_file']['name']);
$mime = $dbLink->real_escape_string($_FILES['uploaded_file']['type']);
$data = $dbLink->real_escape_string(file_get_contents($_FILES ['uploaded_file']['tmp_name']));
$size = intval($_FILES['uploaded_file']['size']);
// Create the SQL query
$query = "
INSERT INTO `file` (
`name`, `mime`, `size`, `data`, `created`
)
VALUES (
'{$name}', '{$mime}', {$size}, '{$data}', NOW()
)";
// Execute the query
$result = $dbLink->query($query);
// Check if it was successfull
if($result) {
echo 'Success! Your file was successfully added!';
}
else {
echo 'Error! Failed to insert the file'
. "<pre>{$dbLink->error}</pre>";
}
}
else {
echo 'An error accured while the file was being uploaded. '
. 'Error code: '. intval($_FILES['uploaded_file']['error']);
}
// Close the mysql connection
$dbLink->close();
}
else {
echo 'Error! A file was not sent!';
}
// Echo a link back to the main page
echo '<p>Click <a href="index.html">here</a> to go back</p>';
?>
list_files.php
<?php
// Connect to the database
$dbLink = new mysqli('localhost', 'root', 'pwd', 'myTable');
if(mysqli_connect_errno()) {
die("MySQL connection failed: ". mysqli_connect_error());
}
// Query for a list of all existing files
$sql = 'SELECT `id`, `name`, `mime`, `size`, `created` FROM `file`';
$result = $dbLink->query($sql);
// Check if it was successfull
if($result) {
// Make sure there are some files in there
if($result->num_rows == 0) {
echo '<p>There are no files in the database</p>';
}
else {
// Print the top of a table
echo '<table width="100%">
<tr>
<td><b>Name</b></td>
<td><b>Mime</b></td>
<td><b>Size (bytes)</b></td>
<td><b>Created</b></td>
<td><b> </b></td>
</tr>';
// Print each file
while($row = $result->fetch_assoc()) {
echo "
<tr>
<td>{$row['name']}</td>
<td>{$row['mime']}</td>
<td>{$row['size']}</td>
<td>{$row['created']}</td>
<td><a href='get_file.php?id={$row['id']}'>Download</a></td>
</tr>";
}
// Close table
echo '</table>';
}
// Free the result
$result->free();
}
else
{
echo 'Error! SQL query failed:';
echo "<pre>{$dbLink->error}</pre>";
}
// Close the mysql connection
$dbLink->close();
?>
get_file.php
<?php
// Make sure an ID was passed
if(isset($_GET['id'])) {
// Get the ID
$id = intval($_GET['id']);
// Make sure the ID is in fact a valid ID
if($id <= 0) {
die('The ID is invalid!');
}
else {
// Connect to the database
$dbLink = new mysqli('localhost', 'root', 'pwd', 'myTable');
if(mysqli_connect_errno()) {
die("MySQL connection failed: ". mysqli_connect_error());
}
// Fetch the file information
$query = "
SELECT `mime`, `name`, `size`, `data`
FROM `file`
WHERE `id` = {$id}";
$result = $dbLink->query($query);
if($result) {
// Make sure the result is valid
if($result->num_rows == 1) {
// Get the row
$row = mysqli_fetch_assoc($result);
// Print headers
header("Content-Type: ". $row['mime']);
header("Content-Length: ". $row['size']);
header("Content-Disposition: attachment; filename=". $row['name']);
// Print data
echo $row['data'];
}
else {
echo 'Error! No image exists with that ID.';
}
// Free the mysqli resources
@mysqli_free_result($result);
}
else {
echo "Error! Query failed: <pre>{$dbLink->error}</pre>";
}
@mysqli_close($dbLink);
}
}
else {
echo 'Error! No ID was passed.';
}
?>
I am not too sure where the error could be but I suspect that it could be somewhere at the add_file or get_file. Seriously hope someone could help me with this bug and thanks for the trouble.
Regards
Jasmine
